Many gas turbine engines operate in harsh environments where the engine can ingest solid particles. Particles can accelerate the deterioration of an engine and reduce the engine’s service life. Understanding particle interactions with the materials used in gas turbines, at representative engine conditions, can improve the design and development of turbomachinery operating in particle laden environments. Coefficient of Restitution (COR) is a measure of the particle/wall interactions and is used to study erosion and deposition. This study presents data taken using the Virginia Tech Aerothermal Rig. Arizona Road Dust (ARD) of 20-40 μm is injected into a flow field to measure the effects of temperature and velocity on particle rebound from a polished high temperature material coupon. The high temperature coupon was tested at different temperatures of ambient (300K), 873K, 1073K, 1173 K, 1223 K, 1273 K, and 1323 K while the velocity of the flow field was held constant at 28 m/s or 70 m/s. The impingement angle of the coupon was varied from 30° to 80° for each temperature tested. The results show an increase in deposition as the temperature approaches the melting temperature of sand. The results have also been compared to previously published literature. / Master of Science

When a gas turbine operates in a particle laden environment, such as a desert, small solid particles are ingested into the engine. The ingested sand particles can cause damage to engine components and reduce the service life of the engine. Particle ingestion causes the erosion of metal blades and vanes, and, if the firing temperature is hot enough, deposition of molten particles in the hot sections of the engine. Both deposition and erosion phenomena can severely reduce overall engine performance. The Coefficient of Restitution (COR) is a measure of the particle-wall interaction, and has been widely used to quantify particle rebound characteristics in past particle impact studies. This work investigates the effects of temperature on sand particle impact characteristics by measuring the COR and other deposition related impact parameters. The first study presented as part of the dissertation contains a description of a novel method used to measure COR using a Particle Tracking Velocimetry (PTV) method. This is combined with Computational Fluid Dynamics (CFD) flow field to allow for an accurate determination of the particle impact velocity. The methodology described in this paper allows for measurement of the COR in a wide range of test conditions in a relatively simple manner. The COR data for two different sizes of Arizona Road Dust (ARD) and one size of glass beads are presented in this paper. Target material was stainless steel 304 and the impact angle was varied from 25 to 85 degrees. The second study details the first quantification of the COR of san particles at elevated temperatures. Temperatures used in this study were 533 K, 866 K, and 1073 K. In this study the mass flow rate through the experimental setup was fixed. This meant that velocity and temperature were coupled. Target material for this study was stainless steel 304 and the impact angle was varied from 30° to 80°. The COR was found to decrease substantially at the temperatures and velocity increased. It was determined that the decrease in COR was almost certainly caused by the increase in velocity, and not the decrease in temperature. The third study contains COR results at elevated temperatures. Significant improvements from the method used to calculate COR in the first paper are described. The particle used for these tests was an ARD sand of 20-40 μm size. Target materials used were stainless steel 304 and Hastelloy X. The particles impinged on the target coupon at a velocity of 28m/s. Tests were performed at three different temperatures, 300 K (ambient), 873 K, and 1073 K to simulate temperatures seen in gas turbine cooling flows. The angle of impingement of the bulk flow sand on the coupon was varied between 30° and 80°. A substantial decrease in COR was discovered at the elevated temperatures of this experiment. Hastelloy X exhibited a much larger decrease in COR than does stainless steel 304. The results were compared to previously published literature. The final study also used the ARD size of 20-40 μm. The target material was a nickel alloy Hastelloy X. Experiments for this study were performed at a constant velocity of 70m/s. Various temperatures ranging from 1073 K up to and including 1323 K were studied. Particle angle of impact was varied between 30° and 80°. Significant deposition was observed and quantified at the highest two temperatures. The COR of the ARD sand at the highest temperatures was found not to change despite the occurrence of deposition. At elevated temperatures, many of the particles are not molten due to sand's non-homogenous and crystalline nature. These particles rebound from the target with little if any change in COR. / Ph. D.

This thesis is an investigation of a doctrine generally known as ‘failure of consideration’, but which I term ‘failure of condition’. I have two principal aims. First, to clarify quite what the doctrine of failure of condition is. Secondly, to explain why it has the effects it does – in particular, why it justifies the response of restitution. The doctrine, at core, concerns conditional transfers: when a transfer is made conditionally, and the condition fails, the transfer can be recovered. For this reason, I term the doctrine ‘failure of condition.’ I investigate the nature of this relationship and argue that the reason why the transfer is conditional is that the agent’s intention to make the transfer was itself conditional. The justification of restitution is a more complex affair than is customarily accepted – but there is a valid justification lurking not far from the surface of orthodoxy. A secondary concern of the thesis is to re-examine an old theory in the field of common mistake, frustration and termination following a breach of contract. It used to be thought that these doctrines could be explained by failure of condition. That theory has fallen out of favour – it seems that no one accepts it today. This rejection rests upon a confusion over the nature of the doctrine of failure of condition. Once the nature of this doctrine has been clarified, we can see how closely the various doctrines align with one another; we can also see where the true difficulty with the failure of condition explanation lies.

The central tenet of tracing theory is that in certain circumstances it is possible to show that one asset stands in the place of another, such that any claims in relation to the original asset can be transmitted to its substitute. Since at least 2001 academic and judicial orthodoxy has been that this is done by following the path of value from one asset to the other, and can be aided in more complex cases by the application of evidential rules or presumptions. These ideas are at the heart of existing accounts of proprietary claims against trustees who deal with trust assets without authority, and personal and proprietary claims against strangers to the trust. They are also at the heart of calls to 'unify' the rules of tracing at law and in equity, removing existing distinctions drawn between claimants who are owed fiduciary duties and those who are not. In this thesis it is argued that there are no independent processes of following and identifying value, and that the language of 'tracing value' has lent the appearance of neutrality and conceptual unity to disparate heads of fiduciary and non-fiduciary liability. Most importantly, it has led to the assumption that in any case in which a claimant can demonstrate that a series of transactions links some right in the defendant’s hands with a right previously held by or for the claimant, the claimant can claim that right. In this thesis it is argued that far from creating an arbitrary practical obstacle for claimants seeking to trace and locate value, the fiduciary relationship is at the heart of the justification for any claim that exists to a new right in the hands of someone else.

Les patients atteints de MICI (maladie de Crohn et recto-colite hémorragique) présentent souvent des lésions des cellules de l'épithélium intestinal. La rémission de ces maladies nécessite à la fois un arrêt de l'inflammation et une migration des entérocytes pour réparer les dommages épithéliaux. Cette migration cellulaire appelée restitution intestinale requiert des adhérences cellule-MEC et cellule-cellule réalisées par les complexes protéiques associés aux intégrines et cadhérines. Le but de cette thèse a été d'étudier l'impact deSaccharomyces boulardii (Sb) sur la réparation de l'épithélium intestinal lésé. Nous avons montré que le surnageant de Sb contenait des facteurs modulant la restitution de l'épithélium intestinal in vivo et in vitro sans affecter la prolifération des cellules épithéliales. Ces effets motogéniques du surnageant de Sb s'exercent via la modulation des molécules d'adhérence. En effet, le surnageant de Sb augmente l'affinité de l'intégrine α2β1 pour son ligand le collagène de type I mais entre en compétition avec les intégrine αvβ5, pour inhiber l'adhérence des entérocytes sur la vitronectine. Ces modifications de l'adhérence avec la matrice extracellulaire entraînent une régulation des voies de signalisation émanant des intégrines et une réorganisation des plaquesd'adhérence. Ces évènements vont accroître la migration des entérocytes. De plus, nos résultats préliminaires portant sur Sb et l'adhérence cellule-cellule durant la restitution intestinale ont montré une implication de la E-cadhérine dans la migration induite par Sb. / Intestinal epithelial cell damage is frequently seen in IBD patients with ulcerative colitis or Crohn's disease. The remission of these diseases requires both the cessation of inflammation and the migration of enterocytes torepair the damaged epithelium. Adhesions with the ECM and the adjacent cells using complex of proteins associated with integrins and cadherins are necessary for this cell migration called intestinal restitution. Theaim of this thesis was to study the effect of S.boulardii on the resealing of a wound in intestinal epithelia. First of all, we demonstrated that the supernatant of S.boulardii contains factors that modulate intestinal epithelial cell restitution both in vitro and in vivo without affecting cell proliferation. We showed that the motogenic factors of S.boulardii act by modulating adhesion molecules. Indeed, the supernatant of S.boulardii increase the the affinity between 21 and it ligand the collagen type I, but also compete with integrin v5 to block theadhesion of enterocytes on vitronectin. These modifications of adhesion on extracellular matrix lead to aregulation of signaling pathway mediated by integrins, and a reorganization of focal adhesions. These eventscontribute to an increase of the migration of enterocytes. Add to this, our preliminaries results on S.boulardiiand cell-cell adhesion during intestinal restitution show an involvement of E-cadherin in the migrationS.boulardii-induced. With this work, we have demonstrated that heat-sensitive motogenic factors secreted by S.boulardii can enhance intestinal restitution with a dynamic regulation of adhesion between integrin and the ECM.

Les espaces scéniques de la Cour de France sont abordés dans la continuité des trois derniers règnes de l’Ancien Régime, à partir d’un ensemble de sources le plus exhaustif possible. Cette nouvelle approche, résolument globale, repose sur le constat que les études précédentes ne se fondaient que rarement sur une identification précise de la nature même des sources qu’elles utilisaient et privilégiaient toujours des sondages ponctuels. A l’inverse, la présente thèse propose d’abord une analyse typologique des sources documentaires, tout particulièrement le considérable fonds des archives de la Maison du roi et des documents textuels, iconographiques et imprimés qu’elle a produits, ainsi que des rares vestiges conservés. Elle met en place des protocoles de travail adaptés à ces sources anciennes et au volume considérable du fonds : restitution virtuelle, base de données-calendrier documentant les lieux de représentation et répétition, interdisciplinarité nécessaire en raison de l’intrication des questions théâtrales, politiques, administratives, artisanales. Un lieu ne peut en effet se comprendre et se restituer sans la connaissance des techniques et méthodes de réalisation, des enjeux curiaux, des pratiques scéniques, et des traditions. La thèse expose quelques résultats significatifs de l’efficacité de cette méthodologie, tant pour le règne de Louis XIV aux sources lacunaires mais souvent considérées comme trop connues, que pour les règnes ultérieurs, très documentés. Notre connaissance des pratiques scéniques, des machines, de l’éclairage, par exemple, s’en trouve enrichie. Apparaît également une constance remarquable des pratiques adaptatives et empiriques de la Cour de France, après la « tabula rasa » de 1659 et les premières voies ouvertes, très vite abandonnées. De la masse des archives comptables, corroborant d’autres sources, se lit enfin une tentative sans fin de la part des Menus-Plaisirs pour gérer efficacement et économiquement une quantité croissante de lieux et matériels, inflation sans doute liée aux prétentions d’une Cour qui se voit comme la plus puissante d’Europe, alors même que la Maison royale ne fait que s’endetter jusqu’en 1789. Cette thèse entend donc ouvrir la voie à de futures recherches sur les spectacles à la Cour de France, ainsi qu’à une meilleure connaissance des lieux grâce aux nouvelles technologies. / The scenic spaces of the Court of France are studied in the continuity of the last three reigns in the Ancien Régime, from a set of sources as exhaustive as it can be. This new approach, global, is induced by the observation that previous studies were rarely based on a precise identification of the very nature of the sources they used and always favored short surveys. Conversely, this dissertation proposes a typological analysis of the documentary sources, especially the huge collection of the archives from the House of the King and the textual, iconographic and printed documents that this administration has produced, as well as rare remains of scenic material. It sets up working protocols adapted to these old sources and to the large volume of the archives : virtual restitution, database-calendar documenting the places for performance and rehearsal, interdisciplinarity required by the entanglement of the theatrical, political, administrative and artisanal ways. A place can not be understood and restituted without the knowledge of the techniques and methods of creation, the curial issues, the stage practice, and the traditions. The dissertation presents some significant results of the effectiveness of this methodology, both for the reign of Louis XIV with its lacunar sources but often considered too well known, as for later reigns, well documented. Our knowledge of scenic practice, machines, lighting, for example, is increased. There is also a remarkable consistency of adaptive and empirical practices of the Court of France, after the "tabula rasa" of 1659 and the first open ways, very quickly abandoned. The collection of accounting records, which corroborate other sources, shows an endless attempt from the Menus-Plaisirs to manage efficiently and economically a growing amount of places and materials, inflation likely linked to the claims of a Court which sees itself as the most powerful in Europe, even though the Royal House is only going into debt until 1789. The dissertation intends to pave the way for future research on shows at the Court of France, as well as to a better knowledge of places, thanks to new technologies.

Zugl.: Jena, Universiẗat, Diss., 2008 u.d.T.: Beckmann, Nina Lorea: Binationale Stiftung und Beutekunst.

This diploma thesis deals with the issue of restitution disputes according to Act No. 229/1991 Coll. on the regulation of ownership relations with land and other agricultural property. The reason for this topic was the experience of the author of the diploma thesis on restitution disputes, scope and judicial jurisprudence dealing with this issue. The thesis deals with the procedural aspects of restitution disputes, as well as with the substantive law-making aspect of both legal regulation and rich judicial jurisprudence. The diploma thesis systematically describes the most important types of restitution disputes - disputes about the restitution of original removed real estate, disputes about the existence of claims of entitled persons to compensation for immovable properties which can not be restituted, disputes about the correct value of claims of authorized persons and disputes about the grant of specific substitute real estates owned by the Czech Republic as a replacement for real estate that can not be restituted. The work emphasizes the breakthrough and current judicial jurisprudence of the Supreme Court of the Czech Republic and the Constitutional Court of the Czech Republic. In the thesis, the author considers the importance of this case law and gives the case law a connection with the...

This diploma thesis deals with the issue of restitution disputes according to Act No. 229/1991 Coll. on the regulation of ownership relations with land and other agricultural property. The reason for this topic was the experience of the author of the diploma thesis on restitution disputes, scope and judicial jurisprudence dealing with this issue. The thesis deals with the procedural aspects of restitution disputes, as well as with the substantive law-making aspect of both legal regulation and rich judicial jurisprudence. The diploma thesis systematically describes the most important types of restitution disputes - disputes about the restitution of original removed real estate, disputes about the existence of claims of entitled persons to compensation for immovable properties which can not be restituted, disputes about the correct value of claims of authorized persons and disputes about the grant of specific substitute real estates owned by the Czech Republic as a replacement for real estate that can not be restituted. The work emphasizes the breakthrough and current judicial jurisprudence of the Supreme Court of the Czech Republic and the Constitutional Court of the Czech Republic. In the thesis, the author considers the importance of this case law and gives the case law a connection with the...

Spatio-temporal variation in activation rates during ventricular fibrillation (VF)provides insight into mechanisms of sustained re-entry during VF. This study had three objectives related to spatio-temporal dynamics in activation rates during VF. The first objective was to quantify spatio-temporal variability in activation rates,that is, in dominant frequencies, computed from epicardial electrograms recorded during VF in swine. Results showed that temporally and spatially, dominant frequencies variedas much as 20% of the mean dominant frequency, and the mean dominant frequencies increased during first 30 sec of VF. These results suggest that activation rates are nonstationary during VF. The second objective of the study was to develop a new stimulation protocol for quantifying restitution of action potential duration (APD) by independently controlling diastolic intervals (DI). A property of cardiac cells that determines spatio-temporal variability in dominant frequencies is restitution of APD, which relates APD to the previous DI. Independent control of DI permits explicit determination of the role of memory in restitution. Restitution functions quantified using mathematical models of activation and our stimulation protocol, showed significant hysteresis. That is, for adiastolic interval, the action potential durations were as much as 15% longer during periods when the DI were decreasing than when the DI were increasing. We verified the feasibility of implementing our protocol experimentally in isolated and perfused rat hearts with action potentials recorded using floating glass microelectrodes. The third objective of our study was to verify that spatio-temporal variability in dominant frequencies during VF could be modified using spatially distributed pacing strength stimuli. Simulated VF was induced in 400x400 and 400x800 matrices of cells. Electrical function of cells was simulated using the Luo-Rudy model. Stimulators were arranged in the matrices such that there were 5 rows of line stimulators. Results showed that it was possible to modify activations in almost 54% of the area and to modify spatio-temporal variability in activation during VF into a desired pattern by the use of synchronized pacing from multiple sites. These results support further exploration of distributed stimulation approach for potential improvements in defibrillation therapy.